The present invention relates to electrical smoking systems and methods of increasing delivery in electrical smoking systems.
Traditional cigarettes are consumed by lighting an end of a wrapped tobacco rod and drawing air predominately through the lit end by suction at a mouthpiece end of the cigarette. Traditional cigarettes deliver smoke as a result of combustion, during which a mass of tobacco is combusted at temperatures which often exceeds 800xc2x0 C. during a puff. The heat of combustion releases various gaseous combustion products and distillates from the tobacco. As these gaseous products are drawn through the cigarette, they cool and condense to form a smoke containing the tastes and aromas associated with smoking. Traditional cigarettes produce sidestream smoke during smoldering between puffs. Once lit, they must be fully consumed or be discarded. Relighting a traditional cigarette is possible but is usually an unattractive proposition to a discerning smoker for subjective reasons (flavor, taste, odor).
In an electrical smoking system, it is desirable to deliver smoke in a manner that meets the smokers experiences with more traditional cigarettes, such as an immediacy response (smoke delivery occurring immediately upon draw), a desired level of delivery (which correlates with FTC tar level), together with a desired resistance to draw (RTD) and consistency from puff to puff and from cigarette to cigarette.
Commonly assigned U.S. Pat. Nos. 5,388,594 and 5,692,525 disclose electrical smoking systems and methods of manufacturing a cigarette, which patents are incorporated by reference. The former patent describes an electrical smoking system including a novel electrically powered lighter and a novel cigarette that cooperates with the lighter. The preferred embodiment of the lighter therein included a plurality of metallic serpentine heaters disposed in a configuration that slidingly receives a tobacco rod portion of the cigarette. The preferred embodiment of the cigarette therein comprised a tobacco-laden tubular carrier, a cigarette paper overwrapped about the tubular carrier, an arrangement of flow-through filter plugs at a mouthpiece end of the carrier and a filter plug at the free (distal) end of the carrier. The cigarette and the lighter were configured such that when the cigarette is inserted into the lighter and as individual heaters are actuated for each puff, localized charring occurs at spots about the cigarette in the locality where each heater was bearing against the cigarette (hereinafter referred to as a xe2x80x9cheater footprintxe2x80x9d or xe2x80x9cchar zonesxe2x80x9d). Once all the heaters had been actuated, the cigarette is discarded.
In the latter patent, the cigarette includes a tobacco plug and the cigarette and the heater fixture are mutually configured such that the heater footprints (char zones) at least partially overlap the tobacco plug as well as a hollow portion of the tobacco rod. Such arrangement provides an immediacy of response from the early initiation of pyrolysis at the void, together with inclusion of a fuller flavor contribution from the plug of tobacco(s).
It has been desirous to produce an electrical smoking system of the type described above that produces delivery levels of substantially greater than 3 milligrams tar (FTC). A greater segment of smokers prefer the higher levels of delivery from their more traditional cigarettes of choice. Obtaining such levels of delivery in electrical smoking systems has heretofore been a challenging proposition.
For example, the previously described electrical smoking systems are battery operated, so that the total energy expended per puff needs to be kept at acceptable levels. Too much power application in the heater elements during a puff can lead to burn-throughs and sometimes undesired degrees of combustion.
In systems such as taught in commonly assigned U.S. Pat. No. 5,692,525, in which heater footprints (char zones) at least partially overlap a hollow portion of the tobacco rod and partially overlap a tobacco plug, burn-throughs will usually first appear in the region of the hollow portion of the tobacco rod. Upon such occurrence, the smoke tends to be hotter than the other puffs, with less contribution of the fuller flavor usually generated by the heating of the tobacco plug portion of the cigarette rod. Consistency in the smoking experience are compromised if burn-throughs are not somehow avoided.
In commonly assigned U.S. Pat. No. 5,388,594, the smoked portion of the tobacco rod is preferably entirely hollow and the heater footprint is entirely superposed over a the hollow portion of the tobacco rod. Burn-throughs in the xe2x80x9cwholly hollowxe2x80x9d system of U.S. Pat. No. 5,388,594 tend to make the smoke all the more hot and/or harsh tasting. Providing expedients to increase delivery in the xe2x80x9cwholly hollowxe2x80x9d system of U.S. Pat. No. 5,388,594, such as providing perforations as suggested at column 10, lines 36-51 thereof, aggravate the risks of burn-throughs, with adverse consequences upon taste and consistency.
Resistance to draw (RTD) of traditional cigarettes is the pressure required to force air through the full length of a cigarette at the rate of 17.5 ml per second. RTD is usually expressed in inches or millimeter of water. Smokers have certain expectations when drawing upon a traditional cigarette in that too little RTD or too much can detract from smoking enjoyment. More traditional cigarettes of moderate delivery have RTD""s generally within the range of approximately 100 to 130 mm water.
Establishing a desired RTD in electrical smoking systems is complicated by the circumstance that in smoking systems such as shown in U.S. Pat. Nos. 5,388,594 and 5,692,525, air is first drawn through passages within the cigarette lighter before being drawn out through the cigarette. The filter tipping of the cigarettes of those systems are preferably flow-through and/or low particulate efficiency filters so as to minimize loss of whatever smoke is produced. Such filters produce little pressure drop and therefore do not contribute much RTD. Consequently, prior practices have included the establishment of RTD (or pressure drop) predominantly in the lighter portion of the electrical smoking system, such as with an annular frit (porous body) adjacent the air admission port of the lighter as taught in commonly assigned U.S. Pat. No. 5,954,979. Because pressure drop varies widely with any change in size of the constriction, it has been found that the use of frits or other forms of tiny flow constrictions in the lighter body must be manufactured with care. It therefore adds expense and other production and quality concerns. Furthermore, tiny flow passages are prone to clog, particularly in lighters wherein any smoke is allowed to linger after completion of a puff.
An object of the present invention is to provide a cigarette containing cut filler or other form of shredded tobacco, which cigarette is adapted to cooperate with an electrical lighter and render satisfying levels of delivery and taste.
Another object of the present invention is to provide a cigarette for an electrical smoking system which includes cut filler, yet provides improved consistency in delivery from puff to puff.
Another object of the present invention is to provide a cigarette adapted for use in electrical smoking systems, which cigarette is resistive to breakage during the withdrawal of the cigarette from the lighter thereof.
It is still a further object of this invention to provide a novel cigarette that is operative with an electrical lighter and conducive to cost-effective methods of manufacture, even at production speeds.
These and other objects are achieved with the present invention which provides an electrical smoking system comprising a cigarette and an electric lighter, wherein the cigarette comprises a tubular tobacco mat partially filled with material tobacco so as to define a filled tobacco rod portion and an unfilled tobacco rod portion. The filled tobacco rod portion is situated adjacent a free end of said cigarette. The lighter comprises an electrical heater element and a system for electrically actuating said heater element, with the lighter being arranged to at least partially receive said cigarette. The cigarette and the lighter are mutually arranged so that when the cigarette is received in the lighter, the electrical heater element of the lighter at least partially superposes at least a portion of the filled tobacco rod portion. The cigarette and the lighter are also mutually arranged so that when the cigarette is received in the lighter, the free end of the cigarette is occluded. Furthermore, the cigarette includes a zone of perforations at a location along the filled tobacco rod portion, with the cigarette being free of perforations along the unfilled tobacco rod portion.
By such arrangements and others, the delivery (total particulate matter (xe2x80x9cTPMxe2x80x9d) per FTC testing methodology) of the electrical smoking system may be increased without producing a hot, harsh-tasting smoke. Importantly, the enhanced delivery is achieved without overdriving the heater element of the lighter. The elevated delivery is achieved without additional load upon the batteries of the lighter and without driving the heater element to excessive peak temperatures.
A further aspect is provision of cooperative features within the lighter and the cigarette such that a large majority of the resistance to draw of the smoking system originates along the side walls of cigarette, with a lesser portion originating from flow passages within the lighter.
A further aspect of the present invention is provision of an air-flow deflector along an interior portion of the lighter to favorably direct air toward the cigarette.
In addition to the above, the invention provides an apparatus for perforating a tobacco rod prior to assembly of the tobacco rod to a filter rod via tipping paper, comprising a drum link-up assembly adapted to transfer a tobacco rod from a combining apparatus to a tipping apparatus wherein the tobacco rod is attached to a filter rod by tipping paper; and a laser perforating apparatus adapted to bum one or more holes in an outer surface of the tobacco rod while the tobacco rod is in the drum link-up assembly.
According to one embodiment of the invention, the laser perforating apparatus includes a lens arrangement which bums at least one circumferentially extending row of perforations around the tobacco rod. According to another embodiment, the drum link-up assembly includes a drum having flutes on an outer surface thereof, the laser perforating apparatus being adapted to rotate the tobacco rod about its axis while pulsing a laser to burn the at least one row of perforations into the tobacco rod as the tobacco rod is rolled from one flute to an adjacent flute. If desired, the laser perforating apparatus can include a beam splitter which separates a beam from a pulsed laser into at least two beams which bum at least two rows of elongated holes into the tobacco rod to form a laser perforated tobacco rod. Preferably, the drum link-up assembly comprises at least one rotating drum having flutes sized to carry 2-up tobacco rods.
According to a preferred embodiment, the drum link-up assembly includes a series of drums which transfer 2-up tobacco rods to the tipping machine, the drums including a catch drum, a transfer drum, a swash plate drum, a laser drum, a cutting drum, and a separating drum, the catch drum receiving 2-up tobacco rods from a delivery device of a combining apparatus and delivering the 2-up tobacco rods to the transfer drum, the transfer drum delivering the 2-up tobacco rods to the swash plate drum, the swash plate drum aligning the 2-up tobacco rods and delivering the aligned 2-up tobacco rods to the laser drum, the laser drum orienting the 2-up tobacco rods such that the laser perforating apparatus bums at least two longitudinally spaced apart rows of perforations on each of the 2-up tobacco rods, the laser drum delivering the 2-up tobacco rods to the cutting drum, the cutting drum cutting the 2-up tobacco rods into a pair of tobacco rods of unit length and delivering the pair of tobacco rods to the separating drum at which the pair of tobacco rods are spaced longitudinally apart, the separating drum delivering the tobacco rods to an assembly drum of a tipping apparatus at which the pair of tobacco rods are combined with a 2-up filter rod by placing the 2-up filter rod between the pair of spaced apart tobacco rods.
The apparatus can further comprise a combining machine which includes means for wrapping a tobacco plug and a free-flow filter plug within a tobacco matt and an outer paper wrapper to form a continuous tobacco rod, the combining machine including a cutting apparatus which cuts the continuous tobacco rod into 2-up tobacco rod segments, the laser perforating apparatus being adapted to burn perforating holes at locations on the 2-up tobacco rods such that the perforating holes pass through the outer paper wrapper and the tobacco matt and into the tobacco plugs of the 2-up tobacco rod segments. Further, the apparatus can include a tipping apparatus which includes means for attaching the perforated tobacco rods to filter rods by locating a 2-up filter rod in a space between a pair of the perforated tobacco rods, wrapping tipping paper around the 2-up filter rod such that the tipping paper overlaps portions of the perforated tobacco rods, gluing ends of the tipping paper together, and cutting the 2-up filter rods to produce a pair of cigarettes. If desired, the tipping apparatus can include a laser perforating station at which the cigarettes are provided with additional perforation holes, the laser perforating station including a lens arrangement which provides at least one circumferentially extending row of the additional perforations at a location along the tobacco rod.
The invention also provides a method of perforating a tobacco rod prior to assembly of the tobacco rod to a filter rod via tipping paper, comprising supplying a tobacco rod to a drum link-up assembly wherein the tobacco rod is moved from a combining apparatus to a tipping apparatus wherein the tobacco rod is attached to a filter rod by tipping paper, and forming a perforated tobacco rod by actuating a laser perforating apparatus so as to burn one or more perforating holes in an outer surface of the tobacco rod while the tobacco rod is in the drum link-up assembly.
Another object of the present invention is to establish a method of manufacturing with high speed production machinery a cigarette of the type operable with an electric lighter and containing cut filler.
It is another object of the present invention to provide a cigarette suited for consumption with a lighter of an electrical smoking system and a method of manufacturing same, wherein the cigarette is not subjected to forces which would tend to collapse or break the cigarette during its manufacture.
It is still a further object of this invention to provide a novel cigarette that is operative with an electrical lighter and a cost-effective method of manufacturing the cigarette.
These objects and other advantages are provided by the present invention which provides a cigarette operable with an electrically operated lighter, which lighter includes a plurality of electrical heaters, with each of the heaters being adapted to, either singularly or in concert, to generate tobacco smoke by applying heat to the cigarette along portions of the cigarette adjacent the heaters as a result of activation of the heater or heaters.
In accordance with one aspect of the present invention, the cigarette comprises a tubular tobacco web, wherein a first portion of the tubular tobacco web is filled with a column of tobacco, preferably in the form of cut filler, and a second portion of the tubular tobacco web is left unfilled or hollow so as to define a void in the tobacco column.
More particularly, the aforementioned cigarette preferably comprises a tobacco rod formed from a tubular tobacco web and a plug of tobacco located within the tubular tobacco web. The tobacco rod is adapted to be slidingly received by an electrical heater fixture such that the heater elements locate alongside the tobacco rod at a location between the free end and an opposite end of the tobacco rod. Preferably the plug (or column) of tobacco extends from the free end of the tobacco rod to a location that is spaced from the opposite end of the tobacco rod so as to define a void (or hollow portion) adjacent the opposite end.
Still another aspect of the present invention is to provide a filler containing cigarette that is operative with an electrical lighter, which cigarette includes a tobacco rod having a free-flow filter and a filler-free rod portion adjacent the free flow filter so as to promote consistent aerosol production.
A preferred embodiment of the present invention provides a method of manufacturing such cigarettes, wherein the method comprises the steps of establishing a succession of 2-up hollow plugs in alternating, spaced apart relation to 2-up tobacco plugs and wrapping the succession of plugs in a tobacco web and overwrap so as to produce a continuous rod; severing the resultant continuous rod to establish associated pairs of singular tobacco rod plugs; separating the members of each associated pair of singular tobacco rod plugs so as to establish a space therebetween; placing a 2-up filter tipping plug in the space between each a pair of separated, singular tobacco rod plugs; bringing the 2-up filter tipping plug and said singular tobacco rod plugs together into an abutting relation; and subsequently wrapping tipping paper about the placed 2-up filter tipping plug together with adjacent portions of the abutting singular tobacco rod plugs to form a 2-up cigarette rod; and severing the 2-up cigarette into individual cigarettes.